We cleaned up the app pages

This isn't about new features. It's about making visible what was already there.

The Hut Calculator, Crypto Prices and Weather pages had no app screenshots at all.
We took new ones on real devices. They now show up in the store list and in link previews too.

Each product now lists its SHA-256 fingerprint. Check the hash of the APK you downloaded
against it and you can confirm for yourself that nobody swapped the file.

We also fixed a few places where the description didn't match the app. The calculator was
listed as having five modes; it has six, and handwriting input wasn't mentioned at all.
For Crypto Prices we added that the kimchi premium comes with the formula, the reference
exchanges, the rate used and the time it was calculated. For Weather we cut the version
history that took up most of the page and wrote about what people actually use, like the
24 solar terms and short-range rainfall.

Fixing only the Korean would leave everyone else reading the old text, so all ten languages
were updated together.